Skip to content 
In the world of screen printing, the exposure calculator is a key player. This gadget helps to ascertain the perfect exposure duration for each screen, taking into account varying factors such as the kind of emulsion used, the intensity of the light source, and its distance from the screen. The objective is to achieve a screen exposure that ensures the emulsion is sufficiently robust for printing, yet can be washed out easily to maintain fine details.
Before you can use an exposure calculator effectively, you need to prepare the screen correctly. This process involves thoroughly cleaning the screens to get rid of ghost images, chemical residues, or leftover ink. Next, the screens must be evenly coated with emulsion for a shiny matte finish, and allowed to dry completely. Details like the mesh count, type of emulsion and mix, exposure times, and screen tension should be noted, as the exposure time relies on these.
The exposure calculator becomes crucial due to the light-sensitive nature of the screen emulsion. This tool aids in establishing the exact light amount necessary to harden the emulsion. Some calculators include exposure tests on a single sheet, offering a visual aid for determining the best exposure time for your setup.
A variety of exposure calculators utilize the step-wedge method, which merges detailed print images from one film with color patches of increasing darkness on another. Overlaying these films demonstrates the emulsion’s reaction to various exposure levels.
It’s important to remember that there’s no universal exposure time for all stencils. Factors such as emulsion stencil thickness, mesh number, and mesh color will alter the exposure duration. To use the calculator proficiently, position it on the screen and expose the screen. Following this, rinse the screen attentively and evaluate the results on the screen. Ideally, you should be able to rinse up to the seventh mark on the calculator (when using the step-wedge method). If you can rinse further or not up to the seventh mark, it suggests that the screen is either underexposed or overexposed.
Exposure calculators like Expo Check by KIWO, Step Wedge Calculator, and DIY Exposure Calculator by Anthem are available in the market. The choice of calculator depends on individual needs, including durability, cost, and ease of operation.
Using an exposure calculator is a sophisticated process that requires a sound understanding of screen preparation and exposure details. Nevertheless, if used correctly, it has the potential to greatly enhance the quality of your screen prints.
How do you calculate screen printing exposure time?
To calculate screen printing exposure time from a DIY Exposure calculator, determine the increments based on the emulsion’s burning speed. For fast-burning emulsions, use short increments of 5-10 seconds. For slower ones, opt for 30-60 second intervals. Create lines at the screen’s top and bottom to indicate the number of separate burn times needed. This method enables accurate exposure timing.
What light is best for screen printing exposure?
UV LED lights are the best option for screen printing exposure. By using photopolymer emulsions and the acceleration of the exposure process, UV LEDs significantly reduce exposure time, leading to improved screen turnaround in any work environment. Enjoy the valuable benefits of shorter exposure time with UV LED lights for screen printing exposure.
